Displaying publications 1 - 20 of 182 in total

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  1. Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Phys Rev Lett, 2014 Apr 25;112(16):161802.
    PMID: 24815637
    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7  fb-1 of proton-proton collision data at s=8  TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass.
  2. Verma N, Dhiman RK, Choudhury A, Taneja S, Duseja A, Singh V, et al.
    Hepatol Int, 2021 Aug;15(4):970-982.
    PMID: 34275111 DOI: 10.1007/s12072-021-10221-7
    BACKGROUND: We evaluated the dynamics of hepatic encephalopathy (HE) and ammonia estimation in acute-on-chronic liver failure (ACLF) patients due to a paucity of evidence.

    METHODS: ACLF patients recruited from the APASL-ACLF Research Consortium (AARC) were followed up till 30 days, death or transplantation, whichever earlier. Clinical details, including dynamic grades of HE and laboratory data, including ammonia levels, were serially noted.

    RESULTS: Of the 3009 ACLF patients, 1315 (43.7%) had HE at presentation; grades I-II in 981 (74.6%) and grades III-IV in 334 (25.4%) patients. The independent predictors of HE at baseline were higher age, systemic inflammatory response, elevated ammonia levels, serum protein, sepsis and MELD score (p 

  3. Mohamed-Zain NA, Jamil K, Penafort R, Singh A, Ibrahim S, Abdul-Rashid AH
    Malays Orthop J, 2021 Jul;15(2):122-128.
    PMID: 34429832 DOI: 10.5704/MOJ.2107.018
    Introduction: To compare the anxiety levels demonstrated by children during cast removal procedure between oscillating saw vs cast shear methods.

    Material and methods: A randomised prospective study of 102 children (mean age 8.3 ± 3.5 years) with fractures involving upper or lower limbs. Children undergoing removal of cast were divided into 2 groups; either by an oscillating saw or a cast cutting shear. The level of anxiety was assessed by recording the heart rate with a portable fingertip pulse oximeter before, during and after removal of the cast. Objective assessment was performed by documenting the fear level on Children's Fear Scale (CFS).

    Results: There was a significant increase in the heart rate of children during cast removal while using the oscillating saw compared to cast shear (p<0.05). The noise level produced by the saw exceeded 80 dB (mean 103.3 dB). The fear level was significantly lower in the cast shear group (p<0.05).

    Conclusion: The noise produced by the oscillating saw was associated with an increased anxiety level in children undergoing cast removal. Cast shear is a simple and inexpensive instrument that can be used for cast removal in overly anxious children.

  4. Maddirevula S, Alsahli S, Alhabeeb L, Patel N, Alzahrani F, Shamseldin HE, et al.
    Genet Med, 2018 12;20(12):1609-1616.
    PMID: 29620724 DOI: 10.1038/gim.2018.50
    PURPOSE: To describe our experience with a large cohort (411 patients from 288 families) of various forms of skeletal dysplasia who were molecularly characterized.

    METHODS: Detailed phenotyping and next-generation sequencing (panel and exome).

    RESULTS: Our analysis revealed 224 pathogenic/likely pathogenic variants (54 (24%) of which are novel) in 123 genes with established or tentative links to skeletal dysplasia. In addition, we propose 5 genes as candidate disease genes with suggestive biological links (WNT3A, SUCO, RIN1, DIP2C, and PAN2). Phenotypically, we note that our cohort spans 36 established phenotypic categories by the International Skeletal Dysplasia Nosology, as well as 18 novel skeletal dysplasia phenotypes that could not be classified under these categories, e.g., the novel C3orf17-related skeletal dysplasia. We also describe novel phenotypic aspects of well-known disease genes, e.g., PGAP3-related Toriello-Carey syndrome-like phenotype. We note a strong founder effect for many genes in our cohort, which allowed us to calculate a minimum disease burden for the autosomal recessive forms of skeletal dysplasia in our population (7.16E-04), which is much higher than the global average.

    CONCLUSION: By expanding the phenotypic, allelic, and locus heterogeneity of skeletal dysplasia in humans, we hope our study will improve the diagnostic rate of patients with these conditions.

  5. Singh A, Priyadarshi K, Raj T, Banerjee T
    Trop Biomed, 2019 Dec 01;36(4):987-992.
    PMID: 33597468
    Blastocystis species (spp.) is an emerging pathogen. There are several unsolved issues linked to this parasite ranging from its nomenclature, commensal status, standardization of laboratory diagnostic methods, genotypes and treatment. Recently, there has been an increase in reports of Blastocystis spp. from symptomatic cases which provide enough evidence of its pathogenic potential. A range of signs and symptoms, from gastro-intestinal to cutaneous manifestations have been attributed to Blastocystis infection. Few reports have established an association between intestinal infection with Blastocystis spp. and skin manifestations in form of urticaria, palmoplantar pruritus and allergy with complete resolution of cutaneous lesions with eradication of the parasite. In this report, we describe a case of Steven Johnson's syndrome (SJS) in a 6 years old girl along with infection with Blastocystis spp. marked by diarrhea and abdominal pain. Stool examination revealed the presence of all forms of the parasite with subsequent decrease in parasite burden and diarrhea over a period of time. Interestingly, the clearance of Blastocystis spp. from stool was followed by recovery from skin lesions and other symptoms. In this case, the course of SJS was clearly associated with Blastocystis infection. Though skin manifestation with Blastocystis infection has been previously reported, this is the first report of its association with SJS. This report indicates newer insights of the parasite that are less well studied.
  6. Tang IP, Periyannan P, Prepageran N, Shashinder S, Singh A, Bhagubhai PN
    Eur J Cancer Care (Engl), 2011 Jan;20(1):93-5.
    PMID: 20088917 DOI: 10.1111/j.1365-2354.2009.01147.x
    We report a very rare case of recurrent nasopharyngeal carcinoma with local involvement of lacrimal sac. The patient was treated with chemotherapy and there was no recurrence noted after 1 year of follow-up.
  7. Arockiaraj J, Easwvaran S, Vanaraja P, Singh A, Othman RY, Bhassu S
    Fish Shellfish Immunol, 2012 May;32(5):929-33.
    PMID: 22361112 DOI: 10.1016/j.fsi.2012.02.011
    This study reports the first full length gene of interferon related developmental regulator-1 (designated as MrIRDR-1), identified from the transcriptome of Macrobrachium rosenbergii. The complete gene sequence of the MrIRDR-1 is 2459 base pair long with an open reading frame of 1308 base pairs and encoding a predicted protein of 436 amino acids with a calculated molecular mass of 48 kDa. The MrIRDR-1 protein contains a long interferon related developmental regulator super family domain between 30 and 330. The mRNA expressions of MrIRDR-1 in healthy and the infectious hypodermal and hematopoietic necrosis virus (IHHNV) infected M. rosenbergii were examined using qRT-PCR. The MrIRDR-1 is highly expressed in hepatopancreas along with all other tissues (walking leg, gills, muscle, haemocyte, pleopods, brain, stomach, intestine and eye stalk). After IHHNV infection, the expression is highly upregulated in hepatopancreas. This result indicates an important role of MrIRDR-1 in prawn defense system.
  8. Arockiaraj J, Easwvaran S, Vanaraja P, Singh A, Othman RY, Bhassu S
    Fish Shellfish Immunol, 2012 Jul;33(1):121-9.
    PMID: 22565019 DOI: 10.1016/j.fsi.2012.04.010
    In this study, we have reported a full length of peroxiredoxin (designated MrPrdx) gene, identified from the transcriptome of freshwater prawn Macrobrachium rosenbergii. The complete gene sequence of the MrPrdx is 940 base pairs in length, and encodes 186 amino acids. MrPrdx contains a long thioredoxin domain in the amino acid sequence between 34 and 186. The gene expressions of MrPrdx in healthy and the infectious hypodermal and hematopoietic necrosis virus (IHHNV) challenged M. rosenbergii were examined using quantitative real time polymerase chain reaction. MrPrdx is highly expressed in all the other tissues of M. rosenbergii considered for analysis and the highest in gills. The expression is strongly up-regulated in gills after IHHNV infection. To understand MrPrdx functional properties, the recombinant MrPrdx protein was expressed in Escherichia coli BL21 (DE3) and purified. A peroxidise activity assay was conducted using recombinant MrPrdx protein at different concentrations. This peroxidises activity showed that the recombinant MrPrdx is a thiol-dependant protein. Additionally, this result showed that recombinant MrPrdx protein, as a secretory protein can remove H₂O₂ and protect DNA damage. This finding leads a possible way to propose the recombinant MrPrdx protein as an effective medicine for reactive oxygen species (ROS) related diseases.
  9. Arockiaraj J, Vanaraja P, Easwvaran S, Singh A, Othman RY, Bhassu S
    Fish Shellfish Immunol, 2011 Dec;31(6):1259-67.
    PMID: 21945707 DOI: 10.1016/j.fsi.2011.09.008
    Apoptosis is genetically programmed cellular killing processes that execute unnecessary or infected cells. It plays an important role in embryogenesis, homeostasis, insect metamorphosis and immunity. Apoptosis inhibitor (MrIAP) was sequenced from the freshwater giant prawn Macrobrachium rosenbergii using Illumina Solexa Genome Analyzer Technique. MrIAP consisted of 1753 base pair nucleotides encoded 535 polypeptide with an estimated molecular mass of 60 kDa. MrIAP amino acid sequence contains IAP superfamily domain between 5 and 490. The deduced amino acid sequences of the MrIAP were aligned with the other IAP family members. The highest sequence similarity was observed in IAP-5 from ant Camponotus floridanus (67%) followed by IAP from body louse Pediculus humanus corporis (66%) and the lowest (62%) in IAP-5 isoform-5 from common chimpanzee Pan troglodytes and IAP-5 from Aedes aegypti. The IAP phylogenetic tree showed that MrIAP closely related to other arthropod blacklegged tick Ixodes scapularis, formed a sister group with IAP from a hemichordate acorn worm Saccoglossus kowalevskii and finally clustered together with IAPs from fish groups. The quantitative real time PCR analysis revealed that significantly (P < 0.05) highest expression was noticed in hepatopancreas and significantly (P < 0.05) lowest expression in pleopods. Based on the results of gene expression analysis, MrIAP mRNA transcription in M. rosenbergii challenged to infectious hypodermal and hematopoietic necrosis virus (IHHNV) was highly induced in hepatopancreas. The collective results of this study indicate that the MrIAP is an essential immune gene and influences the immune response against IHHNV infection in M. rosenbergii.
  10. Arockiaraj J, Easwvaran S, Vanaraja P, Singh A, Othman RY, Bhassu S
    Mol Biol Rep, 2012 Feb;39(2):1377-86.
    PMID: 21614523 DOI: 10.1007/s11033-011-0872-5
    The prophenoloxidase activating system is an important innate immune response against microbial infections in invertebrates. The major enzyme, phenoloxidase, is synthesized as an inactive precursor and its activation to an active enzyme is mediated by a cascade of clip domain serine proteinases. In this study, a cDNA encoding a prophenoloxidase activating enzyme-III from the giant freshwater prawn Macrobrachium rosenbergii, designated as MrProAE-III, was identified and characterized. The full-length cDNA contains an open reading frame of 1110 base pair (bp) encoding a predicted protein of 370 amino acids including an 22 amino acid signal peptide. The MrProAE-III protein exhibits a characteristic sequence structure of a long serine proteases-trypsin domain and an N- and C-terminal serine proteases-trypsin family histidine active sites, respectively, which together are the characteristics of the clip-serin proteases. Sequence analysis showed that MrProAE-III exhibited the highest amino acid sequence similarity (63%) to a ProAE-III from Atlantic blue crab, Callinectes sapidus. MrProAE-III mRNA and enzyme activity of MrProAE-III were detectable in all examined tissues, including hepatopancreas, hemocytes, pleopods, walking legs, eye stalk, gill, stomach, intestine, brain and muscle with the highest level of both in hepatopancreas. This is regulated after systemic infectious hypodermal and hematopoietic necrosis virus infection supporting that it is an immune-responsive gene. These results indicate that MrProAE-III functions in the proPO system and is an important component in the prawn immune system.
  11. Arockiaraj J, Vanaraja P, Easwvaran S, Singh A, Alinejaid T, Othman RY, et al.
    Fish Shellfish Immunol, 2011 Jul;31(1):81-9.
    PMID: 21549198 DOI: 10.1016/j.fsi.2011.04.004
    Arginine kinase-1 (MrAK-1) was sequenced from the freshwater prawn Macrobrachium rosenbergii using Illumina Solexa Genome Analyzer Technique. MrAK-1 consisted of 1068 bp nucleotide encoded 355 polypeptide with an estimated molecular mass of 40 kDa. MrAK-1 sequence contains a potential ATP:guanido phosphotransferases active domain site. The deduced amino acid sequence of MrAK-1 was compared with other 7 homologous arginine kinase (AK) and showed the highest identity (96%) with AK-1 from cherry shrimp Neocaridina denticulate. The qRT-PCR analysis revealed a broad expression of MrAK-1 with the highest expression in the muscle and the lowest in the eyestalk. The expression of MrAK-1 after challenge with the infectious hypodermal and hematopoietic necrosis virus (IHHNV) was tested in muscle. In addition, MrAK-1 was expressed in Escherichia coli by prokaryotic expression plasmid pMAL-c2x. The optimum temperature (30 °C) and pH (8.5) was determined for the enzyme activity assay. MrAK-1 showed significant (P < 0.05) activity towards 10-50 mM ATP concentration. The enzyme activity was inhibited by α-ketoglutarate, glucose and ATP at the concentration of 10, 50 and 100 mM respectively. Conclusively, the findings of this study indicated that MrAK-1 might play an important role in the coupling of energy production and utilization and the immune response in shrimps.
  12. Arockiaraj J, Vanaraja P, Easwvaran S, Singh A, Othman RY, Bhassu S
    Mol Biol Rep, 2012 Jun;39(6):6671-82.
    PMID: 22290288 DOI: 10.1007/s11033-012-1473-7
    In this study, we have reported a full length of small heat shock protein 37 (designated MrHSP37) gene, identified from the transcriptome database of freshwater prawn Macrobrachium rosenbergii. The complete gene sequence of the MrHSP37 is 2,425 base pairs in length, and encodes 338 amino acids. MrHSP37 contains a long heat shock protein family profile in the amino acid sequence between 205 and 288. The mRNA expressions of MrHSP37 in healthy and the infectious hypodermal and hematopoietic necrosis virus (IHHNV) challenged M. rosenbergii were examined using quantitative real time polymerase chain reaction (qRT-PCR). MrHSP37 is highly expressed in hepatopancreas and all the other tissues (walking leg, gills, muscle, stomach, haemocyte, intestine, pleopods, brain and eye stalk) of M. rosenbergii taken for analysis. The expression is strongly up-regulated after IHHNV challenge. To understand its biological activity, the recombinant MrHSP37 gene was constructed and expressed in Escherichia coli BL21 (DE3). The results of ATPase assay showed that the recombinant MrHSP37 protein exhibited apparent ATPase activity which increased with the concentration of the protein. And also the purified recombinant MrHSP37 protein was used for thermal aggregation assay (chaperone activity). It showed that the recombinant MrHSP37 protein is an active chaperone in this assay. Taken together, these results suggest that MrHSP37 is potentially involved in the immune responses against IHHNV challenge in M. rosenbergii.
  13. Arockiaraj J, Easwvaran S, Vanaraja P, Singh A, Othman RY, Bhassu S
    Fish Shellfish Immunol, 2012 May;32(5):670-82.
    PMID: 22293093 DOI: 10.1016/j.fsi.2012.01.013
    In this study, we reported a full length of catalase gene (designated as MrCat), identified from the transcriptome database of freshwater prawn Macrobrachium rosenbergii. The complete gene sequence of the MrCat is 2504 base pairs in length, and encodes 516 amino acids. The MrCat protein contains three domains such as catalase 1 (catalase proximal heme-ligand signature) at 350-358, catalase 2 (catalase proximal active site signature) at 60-76 and catalase 3 (catalase family profile) at 20-499. The mRNA expressions of MrCat in healthy and the infectious hypodermal and hematopoietic necrosis virus (IHHNV) challenged M. rosenbergii were examined using quantitative real time polymerase chain reaction (qRT-PCR). The MrCat is highly expressed in digestive tract and all the other tissues (walking leg, gills, muscle, hemocyte, hepatopancreas, pleopods, brain and eye stalk) of M. rosenbergii taken for analysis. The expression is strongly up-regulated in digestive tract after IHHNV challenge. To understand its biological activity, the recombinant MrCat gene was constructed and expressed in Escherichia coli BL21 (DE3). The recombinant MrCat existed in high thermal stability and broad spectrum of pH, which showed over 95% enzyme activity between pH 5 and 10.5, and was stable from 40 °C to 70 °C, and exhibited 85-100% enzyme activity from 30 °C to 40 °C.
  14. Arockiaraj J, Easwvaran S, Vanaraja P, Singh A, Othman RY, Bhassu S
    Fish Shellfish Immunol, 2012 Jan;32(1):161-9.
    PMID: 22119573 DOI: 10.1016/j.fsi.2011.11.006
    Caspase 3c (MrCasp3c) was sequenced from the freshwater giant prawn Macrobrachium rosenbergii using Illumina Solexa Genome Analyzer Technique. MrCasp3c consisted of 2080 bp nucleotide encoded 521 polypeptide with an estimated molecular mass of 59 kDa. MrCasp3c sequence contains caspase family p20 domain profile and caspase family p10 domain profile at 236-367 and 378-468 respectively. The quantitative real time PCR analysis revealed a broad expression of MrCasp3c with the highest expression in haemocyte and the lowest in stomach. The expression of MrCasp3c after challenge with the infectious hypodermal and haematopoietic necrosis virus (IHHNV) was tested in haemocyte. In addition, MrCasp3c was expressed in Escherichia coli by prokaryotic expression plasmid pMAL-c2x. The enzyme activity of MrCasp3c was also found to be up-regulated by IHHNV in haemocyte and hepatopancreas tissues. This study suggested that MrCasp3c may be an effector caspase associated with the induction of apoptosis which is potentially involved in the immune defence of M. rosenbergii.
  15. Singh A, Bhatt P
    J Pharmacol Pharmacother, 2012 Jul;3(3):228-32.
    PMID: 23129957 DOI: 10.4103/0976-500X.99417
    Despite comprehensive and stringent phases of clinical trials and surveillance efforts, unexpected and serious adverse drug reactions (ADRs) repeatedly occur after the drug is marketed. ADR reporting is an important aspect of an efficient and effective pharmacovigilance program. Although Medwatch, Yellow Card, CDSCO form, etc. are the protocol forms of ADR collection and reports, a number of countries design and use their respective ADR forms. This review compares similarities and dissimilarities of 13 ADR forms of countries representing their geographical location. This study extracted 73 data elements mentioned in 13 different ADR forms. Only 13 elements were common. An ADR form of Malaysia and Canada covers the highest number of data 43, while Brazil falls to the opposite end with a number of 17 data elements in lieu with the Generic ADR Form. The result of this review highlights 58 data elements of the proposed generic ADR form which ensures that requisite reporting information essential for correct causality assessment of ADRs are included. The proposed "Generic ADR form" could be adopted worldwide mandatorily for reporting any/all ADRs associated with marketed drugs.
  16. Waryam Singh Malhi FSA, Sugathan S, Binti Azhar NAS, Binti Wan Roslan WIN, Abu Bakar HAB, Binti Zolkaine SM
    Educ Health (Abingdon), 2021 12 24;34(2):55-63.
    PMID: 34937299 DOI: 10.4103/1357-6283.332958
    Background: Sexual harassment (SH) may occur anywhere in the world, including the hospital setting. Medical and nursing students are not excluded from being sexually harassed during their clinical practice. This study examined the experiences and compared the perception of SH between female medical and nursing students during their clinical practice in Perak, Malaysia.

    Methods: A comparative cross-sectional study design was done among female medical and nursing students during their clinical practice.

    Results: Total respondents were 481 female medical and nursing students (response rate of 96.2%). About 17.8% of medical and 18.8% of nursing students had been sexually harassed. The most common harasser for medical and nursing students were males (51.2% and 48.8%, respectively), patients (39.7% and 60.3%, respectively), age 30s (41.0% and 59.0%, respectively) and 40s (65.5% and 34.5%, respectively), occurred in medical wards for both groups (50% each). From the SH checklist, 76.9% of medical and 73.5% of nursing students had experienced at least one item of the total 18 items. The abnormal sexual desire of an individual was chosen as the reason for SH by 44.9% of medical and 33.8% of nursing students. The majority of respondents said the issue of SH in clinical practice was very serious. Around 32% of medical students choose the fear of being disadvantaged during clinical practice as the reason why the victims kept quiet while 41.5% of nursing students chose because of not having evidence. Both groups of students suggested establishing rules and laws relating to SH (30.8% and 35.5%, respectively) as effective methods to prevent it. About 75.3% of medical and 81.6% of nursing students agreed that it was very necessary for implementing a SH prevention program.

    Discussion: Although SH is not a new issue, there is insufficient exposure about SH among medical and nursing students. This can be corrected by increasing their knowledge and awareness about SH.

  17. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2020 Sep 04;125(10):102001.
    PMID: 32955327 DOI: 10.1103/PhysRevLett.125.102001
    The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):152001.
    PMID: 33095627 DOI: 10.1103/PhysRevLett.125.152001
    Using a data sample of proton-proton collisions at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} collected by the CMS experiment in 2016-2018, the B_{s}^{0}→X(3872)ϕ decay is observed. Decays into J/ψπ^{+}π^{-} and K^{+}K^{-} are used to reconstruct, respectively, the X(3872) and ϕ. The ratio of the product of branching fractions B[B_{s}^{0}→X(3872)ϕ]B[X(3872)→J/ψπ^{+}π^{-}] to the product B[B_{s}^{0}→ψ(2S)ϕ]B[ψ(2S)→J/ψπ^{+}π^{-}] is measured to be [2.21±0.29(stat)±0.17(syst)]%. The ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{0}→X(3872)K^{0}] is found to be consistent with one, while the ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{+}→X(3872)K^{+}] is two times smaller. This suggests a difference in the production dynamics of the X(3872) in B^{0} and B_{s}^{0} meson decays compared to B^{+}. The reported observation may shed new light on the nature of the X(3872) particle.
  19. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Dec 14;121(24):241802.
    PMID: 30608761 DOI: 10.1103/PhysRevLett.121.241802
    Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B→D^{(*)}τν, hints of lepton universality violation in B→K^{(*)}ℓℓ decays, and the anomalous magnetic moment of the muon, can be explained by the existence of leptoquarks (LQs) with large couplings to third-generation quarks and masses at the TeV scale. The existence of these states can be probed at the LHC in high energy proton-proton collisions. A novel search is presented for pair production of LQs coupled to a top quark and a muon using data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9  fb^{-1}, recorded by the CMS experiment. No deviation from the standard model prediction has been observed and scalar LQs decaying exclusively into tμ are excluded up to masses of 1420 GeV. The results of this search are combined with those from previous searches for LQ decays into tτ and bν, which excluded scalar LQs below masses of 900 and 1080 GeV. Vector LQs are excluded up to masses of 1190 GeV for all possible combinations of branching fractions to tμ, tτ and bν. With this analysis, all relevant couplings of LQs with an electric charge of -1/3 to third-generation quarks are probed for the first time.
  20. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Nov 30;121(22):221802.
    PMID: 30547617 DOI: 10.1103/PhysRevLett.121.221802
    The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at sqrt[s]=13  TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9  fb^{-1}. Events are selected by requiring the presence of a muon (μ), a photon (γ), an imbalance in transverse momentum from an undetected neutrino (ν), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the background-only hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is σ(pp→tγj)B(t→μνb)=115±17(stat)±30(syst)  fb, which is consistent with the standard model prediction.
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